We used the inverted parallaxes as a distance estimate when calculating the interstellar absorption. However, [1]} have shown that the Gaia DR2 parallaxes can be biased. We compared the distances estimated via Gaia DR2 trigonometric parallaxes and the ones of [1]} which are obtained by a statistical method to see the impact of the distances of the stars on the analysis, as explained in the following. The mean of the differences between the distances estimated by two procedures and the corresponding standard deviation are -0.10 pc and 0.66 pc, respectively. As seen Fig. 10, almost all distances fit with the one-to-one straight line. Hence, we do not expect any systematic uncertainty for our results.
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